Use of Satellite Data to Map Flood Extension Around the City of Saint-Louis in the Senegal River Estuary

In this project the issue of flood hazard mapping has been addressed from the perspective of different mapping scale in a GIS environment. The flood hazard map is particularly handy for the planners and administrators for formulating remedial strategy

Co-transmission of related parasite lineages shapes within-host parasite diversity

Malaria patients frequently carry one or more clonal lineage of the parasite, Plasmodium falciparum. In regions of high transmission, we might expect component parasites within complex infections to be unrelated as a result of parasite inoculations from different mosquitos. This project was designed to directly test this prediction. We generated 485 near-complete single-cell genome sequences isolated from fifteen P. falciparum patients from Chikhwawa, Malawi, an area of intense malaria transmission. Matched single-cell and bulk genomic analyses revealed that patients harbored up to seventeen unique lineages. Current statistical approaches were unable to accurately reconstruct infection composition from bulk sequence data. Surprisingly, our analysis demonstrated that parasite lineages within infections tend to be related, suggesting that superinfection by repeated mosquito bites is rarer than co-transmission of parasites from a single mosquito. Our single-cell analysis indicates strong barriers to establishment of secondary infections, providing new insights into the biology and transmission of malaria

Efficient Graph-Oriented Summary for Optimized Resource Description Framework Streams Processing Using Extended Centrality Measures

International audienceExisting RDF Stream Processing (RSP) systems allow continuous processing of RDF data issued from different application domains such as weather station measuring phenomena, geolocation,IoT applications, drinking water distribution management and so on. However processing window phase often expires before finishing the entire session and RSP systems immediately delete data streams after each processed window. Such mechanism does not allow an optimized exploitation of the RDF data streams as the most relevant and pertinent information of the data is often not used in a due time and almost impossible to be exploited for further analyzes. It should be better to keep the most informative part of data within streams while minimizing the memory storage space. In this work, we propose an RDF graph summarization system based on an explicit and implicit expressed needs through three (3) main approaches: (1) an approach for user queries (SPARQL) in order to extract their needs and group them into a more global query, (2) an extension of the closeness centrality measure issued from Social Network Analysis (SNA) to determine the most informative parts of the graph and (3) an RDF graph summarization technique combining extracted user query needs and the extended centrality measure. Experiments and evaluations show efficient result in term of memory space storage and the most expected approximate query results on summarized graphs compared to the source ones.Existing RDF Stream Processing (RSP) systems allow continuous processing of RDF data issued from different application domains such as weather station measuring phenomena, geolocation,IoT applications, drinking water distribution management and so on. However processing window phase often expires before finishing the entire session and RSP systems immediately delete data streams after each processed window. Such mechanism does not allow an optimized exploitation of the RDF data streams as the most relevant and pertinent information of the data is often not used in a due time and almost impossible to be exploited for further analyzes. It should be better to keep the most informative part of data within streams while minimizing the memory storage space. In this work, we propose an RDF graph summarization system based on an explicit and implicit expressed needs through three (3) main approaches: (1) an approach for user queries (SPARQL) in order to extract their needs and group them into a more global query, (2) an extension of the closeness centrality measure issued from Social Network Analysis (SNA) to determine the most informative parts of the graph and (3) an RDF graph summarization technique combining extracted user query needs and the extended centrality measure. Experiments and evaluations show efficient result in term of memory space storage and the most expected approximate query results on summarized graphs compared to the source ones

Quality assessment of malaria microscopic diagnosis at the Aristide Le Dantec University Hospital of Dakar, Senegal, in 2020

Abstract Background Following WHO guidelines, microscopy is the gold standard for malaria diagnosis in endemic countries. The Parasitology-Mycology laboratory (LPM) is the National Reference Laboratory and is currently undergoing ISO 15189 accreditation. In this context, we assessed the performance of the laboratory by confirming the reliability and the accuracy of results obtained in accordance with the requirements of the ISO 15189 standards. This study aimed to verify the method of microscopic diagnosis of malaria at the LPM, in the Aristide Le Dantec hospital (HALD) in Dakar, Senegal. Methods This is a validation/verification study conducted from June to August 2020. Twenty (20) microscopic slides of thick/thin blood smear with known parasite densities (PD) selected from the Cheick Anta Diop University malaria slide bank in Dakar were used for this assessment. Six (6) were used to assess microscopists’ ability to determine PD and fourteen (14) slides were used for detection (positive vs negative) and identification of parasites. Four (4) LPM-HALD microscopists read and recorded their results on prepared sheets. Data analysis was done with Microsoft Excel 2010 software. Results A minimum threshold of 50% concordance was used for comparison. Of the twenty (20) slides read, 100% concordance was obtained on eight (8) detection (positive vs negative) slides. Four (4) out of the six (6) parasite density evaluation slides obtained a concordance of less than 50%. Thirteen (13) out of the fourteen (14) identification slides obtained a concordance greater than 50%. Only one (1) identification slide obtained zero agreement from the microscopists. For species identification a concordance greater than 80% was noted and the microscopists obtained scores between 0.20 and 0.4 on a scale of 0 to 1 for parasite density reading. The microscopists obtained 100% precision, sensitivity, specificity and both negative and positive predictive values. Conclusion This work demonstrated that the microscopic method of malaria diagnosis used in the LPM/HALD is in accordance with the requirements of WHO and ISO 15189. Further training of microscopists may be needed to maintain competency

Risques climatiques et agriculture en Afrique de l’Ouest

Le futur de l’Afrique de l’Ouest dépend de la capacité du secteur de l’agriculture à s’adapter pour garantir la sécurité alimentaire dans un contexte de changement climatique et de croissance démographique. Pour faciliter cette adaptation, la recherche a déployé d’importants efforts pour améliorer les connaissances sur les mécanismes climatiques et leurs impacts sur les systèmes agropastoraux. Or, ces avancées issues de la recherche ne sont que rarement prises en compte dans la planification et la prise de décision. Partant de ce constat, un projet de recherche « Agriculture et gestion des risques climatiques : outils et recherches en Afrique », soutenu par le ministère français des Affaires étrangères et du Développement international est mené entre 2016 et 2018 dans plusieurs pays d’Afrique de l’Ouest. Il a pour objectif d’élaborer des outils efficaces de gestion du risque climatique pour les agriculteurs, en co-construisant avec des réseaux de chercheurs et d’acteurs directement impliqués dans l’accompagnement de l’agriculture des stratégies innovantes basées sur les résultats de la recherche. Cet ouvrage restitue les principales avancées de cette recherche-action sur trois thématiques prioritaires : les services climatiques pour l’agriculture, la gestion des ressources en eau et l’intensification écologique. Il permet aux acteurs du secteur agricole (organisations paysannes, filières, secteur privé agricole, banques de développement agricole, fournisseurs d’intrants, services agricoles et de météorologie) de s’approprier de nouvelles connaissances et de nouveaux outils pour une meilleure prise en compte des risques climatiques dans la gestion des systèmes de production